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Monday, 3 November 2014

Canadian Geographic just released their special magazine devoted to the discovery of HMS "Erebus". It's a comprehensive issue filled with articles by members of the discovery team and some of the world's foremost Franklin researchers. It also includes some wonderful graphics, including never before seen photographs of the discovery.

I'm happy to report that Canadian Geographic asked to use my plans for their article on the ships, and if you buy the magazine you can see a custom version of HMS Terror's outboard profile, which is an updated version of a plan I produced many months ago.

Monday, 6 October 2014

“The Erebus and Terror were both bomb vessels. They seem to be twin ships alike in build, in colours, in masts, and rigging, and, indeed, in every external appearance. An inexperienced eye could not tell the one from the other” (Anonymous 1839:405).

Most readers of this blog will now be aware that Parks Canada has identified their recent discovery as HMS Erebus. There has been significant speculation about how Erebus and Terror might have differed, but few comprehensive accounts have been written. I have outlined a great deal of information about the differences between the ships in previous posts, and thought I would take the opportunity to collate that information here. The ship plans and related historical documents provide a relatively clear account of their differing construction and subsequent standardization as polar exploration vessels. A holistic look at the historical data indicates that by 1845 the differences between the two vessels were very subtle indeed. Construction Details:

Name

Class

Designer

Builder

Laid Down

Launched

Burthen

Terror

Vesuvius (Bomb)

H. Peake

Topsham, Davy

Sept 1812

June 29, 1813

326 tons

Erebus

Hecla (Bomb)

H. Peake

Pembroke, Royal Navy

Oct 1824

June 7, 1826

372 tons

Size:

Hecla class bomb vessels were a slightly larger version of Peake’s earlier Vesuvius class design, the most notable difference being a fuller, more bluff, bow. In fact, the roots of the Hecla class can be seen in penciled-in annotations on the 1812 plans for HMS Vesuvius. The rationale behind the change appears to have been to address the poor sailing qualities of the Vesuvius class and the subsequent need to store more ballast to improve stability (Ware 1994:67). The inability of the Vesuvius class to carry sail in weather would plague the Terror throughout its career (see below).

The table below provides measurements of the general dimensions of the vessels and how these changed over time. Each of the measurements were taken directly from the plans, which I corrected for distortion and precisely scaled to the ¼ inch (1:48) Admiralty standard (to the extent possible given draughtsman’s errors). In the case of the Erebus, I did not have access to the original 1826 draughts, so I have cited dimensions reported in other sources (e.g. Ware 1994). Two of the measurements (moulded breadth and length of the gun [lower] deck) conform to standard nautical measurements, while the remainder are provided to demonstrate the overall size differences between the vessels.

It is important to recall that the sterns of both vessels were each modified twice; first in 1836/1839 to accommodate new rudder configurations, and again in 1845 to permit the fitting of the new screw propeller system. We have precise data on how the 1845 modifications affected the length of Terror, but not of Erebus. Here I have estimated the length of the Erebus in 1845 by applying the same change in length calculated for HMS Terror. How accurate this estimate might be is unknown, but it should be generally applicable.

Measurement

Terror 1813

Erebus 1826

Terror 1836/1839

Erebus 1839

Terror 1845

Erebus 1845

Difference

1845

Length of Upper Deck

107’ 2”

-

109’ 8”

111’ 3”

108’ 6”

110’ 1” *

1’ 7” *

Breadth of Upper Deck

25’ 7”

26’ 4”

25’ 7”

26’ 4”

25’ 7”

26’ 4”

9”

Length of Lower Deck

102’

105’

101’ 3”

104’ 5”

102’

105’ *

3’ *

Moulded Breadth

27’ 3”

28’ 10”

27’ 3”

28’ 10”

27’ 3”

28’ 10”

1’ 7”

Height of Upper Deck From Bottom of False Keel (amidships)

22’ 0”

-

23’ 6”

24’ 1”

23’ 6”

24’ 1”

7”

Basic size comparison of the Terror and Erebus (* denotes an estimated value).

The table shows that, overall, the size differences between the ships were very small, a matter of inches in many cases.

As I have discussed previously, I believe that the ships underwent a process of standardization in 1839, following Parry’s scheme of outfitting exploration fleets with identical equipment. We have good primary evidence for this written directly on the 1839 plans, which are labelled “HMS Terror and Erebus,...as fitted”. However, these plans are known to be based on the dimensions of HMS Erebus, and therefore questions have endured about how accurately the plans depict the fittings on HMS Terror. Below, I outline evidence that the Terror was outfitted almost precisely as depicted in the 1839 plans.

Deck Structures, Fittings, and Their Positions:

As outlined above, the titles of the 1839 plans indicate that both vessels were outfitted in the same manner, meaning that the deck fittings, hardware, and their positions should have been practically identical. However, the 1836 Terror plans show that important structures like hatchways and ladderways were located in radically different positions in 1836. Moving these would have required an extensive refit, and this raises valid doubts that important structural components were not moved on Terror. If they were not moved, logic dictates that their design was not changed as well. Perhaps other minor fittings were not modified either.

However, there is good primary evidence indicating that many of Terror's deck structures were moved and/or rebuilt to the 1839 standard. Though very faint today (and almost entirely invisible on the printed plans from the NMM), the 1836 Terror plans are heavily annotated with pencil markings. Colour and contrast correcting of the digital copies of the plans makes these markings easily visible, and shows many instances where structures were crossed out and moved. For example, the fore hatch on the 1836 plans was scratched out and moved to a more forward position, its size and position matching the 1839 plans precisely. Corresponding changes are shown below decks as well, indicating that lower deck hatches were moved to positions shown on the 1839 plans. Above decks, the companionway structure aft of the main mast was similarly scratched out, indicating that a new structure was built. The same occurred on the aft deckhouse(s), which appear to have been changed to a taller version.

Additionally, the paired midships pumps were crossed out on the 1836 HMS Terror plans, suggesting these too were changed to the Massies’ Patent pumps shown on the 1839 plans, a fact confirmed by contemporary newspaper articles (Anonymous 1839:405). There are no such markings on the capstan, windlass, or galley stove on the 1836 Terror plans, nor was the failed hot-water furnace struck from the plans. However, we know that the furnace was upgraded in 1839 because there is a report of it catching on fire (Davis 1901:20). Given this evidence, I think it is prudent to assume that other critical pieces of equipment were also upgraded with the Erebus in 1839.

Having outlined these similarities, it is important to note that because of its slightly smaller size, the position of deck fittings on Terror did differ somewhat from the Erebus. The following image illustrates some of these positional differences.

Example of the subtle difference in position of the skylights and mizzenmast on the two ships, measured from the position of the stem rabbet. The red indicates Erebus, the green is Terror.

Bowsprit:

Reports from the Antarctic expedition (Ross 1847a; 1847b) indicate that Terror could not carry as much sail as Erebus and was constantly falling behind. Davis, Second Master on HMS Terror during the Antarctic expedition, indicates that part of the problem was that Terror’s bowsprit was too low (Davis 1901:17). Green-ink annotations on the 1836 Terror plans show that Oliver Lang fixed this problem in 1845 by raising Terror’s bowsprit by approximately 4.5 feet. This required that the bowsprit partners be moved nearly six feet aft, almost to the position of the foremast. The Erebus, with its higher draught and bowsprit, did not require this modification. The position of the bowsprit partners may have been the most drastic difference on the deck of the ships.

Plan highlighting the difference in position of the foremast and bowsprit partners. The red indicates Erebus, the green is Terror.

Anchors:

The 1839 plans provide a list of the ten anchors required for each vessel. The largest anchors were identical in size, but the list shows that the kedges and smaller anchors differed, with the Terror’s being slightly smaller on all accounts.

Hull Fittings:

The 1836 plans for HMS Terror, as well as contemporary images from the Back voyage, seemingly indicate some external differences in the vessels. Specifically, in 1836 the solid ice channels and bulwarks on the Terror had gaps that did not exist on the Erebus. However, contemporary images of the Terror from both the Ross and Franklin voyages by Davis and Stanley, respectively, indicate that these gaps were closed on the Terror as per the 1839 plans.

There have been similar questions about the use of iron reinforcements on the catheads on the Terror as the 1836 plans show a wooden crutch instead of the iron version shown on the 1839 plans. Again, it is reasonable to propose that such a seemingly minor fitting may not have been changed in 1839. However, we know that at least one of Terror’s catheads was destroyed in 1842 (Davis 1901: 27), and it seems likely that "modern" iron reinforcements would have been used when the cathead was repaired, as these structures were obviously vulnerable.

Internal Strengthening:

The 1839 cross section plan shows a system of iron knees common on Royal Navy vessels of the period. In fact, the system is precisely the same as that introduced in the early 19th century by Sir Robert Seppings (a design for which he was awarded the Copley Medal from the Royal Society). However, debate persists that Terror did not have iron knees, because the 1836 plans include a cross-section that does not show them. This must have been an error of the draughtsman, because the 1836 cross section (and profile) shows the precise shelf and clamp system Seppings devised for use exclusively with iron knees. In short, there would be no reason to implement this system of shelf-pieces and clamps without iron knees (for reference, consult Goodwin 1987:80).

However, one specific difference in internal strengthening is shown in the 1839 cross section plans. It appears that two massive wooden riders which extended from the hold to the orlop deck were installed in HMS Terror in 1839. The reason for these riders is not recorded, but accounts by Davis written in 1842 (1901:19) indicate that the Terror had been severely weakened from the trauma of the Back voyage and such reinforcement might have been prudent on the aging and long-suffering Terror.

In Sum:

As quoted above, a newspaper report of the Ross Antarctic expedition stated that the Franklin vessels were "twin ships alike in build, in colours, in masts, and rigging, and, indeed, in every external appearance. An inexperienced eye could not tell the one from the other” (Anonymous 1839:405). Given the data presented above, I believe this to be a very accurate statement. The ships were originally designed and built, and then refitted, to be essentially identical - with just several inches separating them in most dimensions. Hopefully, the discovery of HMS Terror by Parks Canada in coming years will shed further light on contrasts between the ships.

Davis, J.E. 1901 A Letter From the Antarctic. William Clowes & Sons, London.Ross, Sir James Clark

1847a A Voyage of Discovery and Research in the Southern and Antarctic Regions, During the Years 1839-1843: Volume I. John Murray, London.1847b A Voyage of Discovery and Research in the Southern and Antarctic Regions, During the Years 1839-1843: Volume II. John Murray, London.Ware, Chris.1991 The Bomb Vessel: Shore Bombardment Ships of the Age of Sail. Naval Institute Press, Annapolis.

Wednesday, 17 September 2014

By now, most regular readers of this blog will know about Parks Canada’s discovery of one of Franklin’s ships and most will likely have seen the beautifully detailed sonar images of the vessel. My blog has received more visits in the last week than it has in the past six months and I’ve received many emails and comments asking for my thoughts on the identity of the vessel. I’m gratified that readers think that my plans could be useful, but I won’t be speculating here on the identity of the ship - that is something that should be left to the professionals. Regardless, it is possible to comment on some of the information already released. The most thrilling is the movie posted of the wreckage, and the identification of two cannons within it. Royal Navy exploration vessels commonly carried a contingent of small cannons and signal guns. For example, the contemporary HMS Beagle carried up to 8 guns on her second voyage in 1832, a mix of smaller caliber brass carriage guns and carronades. We have no primary information (that I am aware of) describing how many cannons Franklin’s ships may have carried for their 1845 voyage, but some information exists about their armament for the 1839 Antarctic voyage. A widely distributed, and generally accurate, newspaper account of the time states (Anonymous 1839):

From this account it appears that the ships may have each had the same number of relatively small cannons, likely located along recesses in the bow and midships sections of the deck. These would have been useful for signalling, especially during foul weather. As well, because these were Royal Navy vessels, they would have required some defensive armament, no matter how slight. Another fascinating find associated with the discovery was a u-shaped iron crutch/pintle for the ship’s davit stanchion (a piece fitted inside the bulwarks to support the raising and lowering of the davit arm). The Erebus and Terror each had ten of these stanchions, located along both sides of the vessels. The image below was extracted from plans I developed some time ago, but I’m pleased that it appears to correspond nicely in size and shape to the actual piece. It is remarkable how accurate the plans appear to have been for these vessels, though deciphering the many modifications can be mind-numbing.

Configuration of the davit stanchion on the Franklin vessels (the left shows the
outboard profile and the right shows the cross section). The iron pintle/crutch
at the heel supported the entire structure and secured it to the bulwarks;
therefore it needed to be robust.

As posted previously, I've posited that by 1845 the vessels had been fitted in a virtually identical fashion. The 1839 plans, labeled "Terror and Erebus, as fitted", seem to imply this, though some critical differences might have existed. Despite the fact that Erebus belonged to the slightly larger Hecla and Terror to the smaller Vesuvius Class, both ships had been extensively modified and their lengths altered due to a reconstruction of their sterns. This makes identifying the wreck from the confusing corpus of plans (most of which are heavily annotated) a daunting task, and I’m looking forward to hearing which of the two vessels they have discovered! References: Anonymous 1839 The Antarctic Expedition. Gentleman’s Magazine 12:405-407.

Saturday, 6 September 2014

As part of my research on the Terror’s lower deck, I created a series of elevations of the fittings and accommodations. In my previous post, I provided a cross section of the captain’s great cabin, which was the most spacious and lavishly appointed room on the ship. This stood in contrast to Crozier’s bed cabin which appears to have been as small and spare as the other officer cabins (in fact, it was among the smaller bed cabins on the vessel). It had just enough space for a simple bed, a washstand, and a small fixed writing table (in contrast to the larger folding writing tables in the other cabins).

This elevation is based on details derived from the Terror’s 1836 lower deck plans (modified in 1845), the somewhat more detailed 1839 lower deck plans, and the 1839 midships section plan. Further information was taken from images of fittings on HMS Unicorn, HMS Trincomalee, and HMS Warrior.

The cross section shown here provides some interesting information about how the ship was modified for polar exploration. The square-shaped hot air heating funnel can be seen just behind the bed. Heated air must have escaped from holes in the upper surface of the funnel, rising through the space between the bed and the spirketting caused by the knee, as the 1836 plans (and others) show that these beds were built flush to the deck. The “thick” waterway was fitted in 1836 and, in addition to its traditional function of protecting the beam and plank ends, worked as a sort of reverse shelf piece/deck clamp to support strain on the decks from ice pressure. The six inch thick shelf piece itself was as robust as ships of 60 to 90 guns, and its run and position is specifically noted on both the 1836 and 1839 profile plans, suggesting it was a new modification to both ships. The right-angle iron knee was a relatively standard design of the era and examples can be found on the gun deck of Seppings' HMS Unicorn. We know similar knees were retrofitted to HMS investigator and I expect the same occurred on the Terror, and the partial section on the 1836 plans shows a clamp/shelf design commonly used with iron knees (although the iron kneeisn't shown until the 1845 midships section). The knee was bolted to the beam, the bolts passing through the shelf piece, the chock, the frame, and the first layer of the outside hull planking. Uniquely, its heel was supported by a massive six inch thick plank bolted to the spirketting. Again, the run of this plank was shown on both the 1836 and 1839 profile plans, suggesting it was a critical modification to both ships. On the Investigator, both the shelf piece and the supporting plank below the chock were made from elm, but Rice (Ross 1847) indicates they were made of oak on the Franklin vessels .

The massive knees severely impacted the available space in the cabins, and the iron knee itself must have been a constant source of discomfort to Crozier’s sleep. In a personal letter to his friend and former commander, James Clark Ross, Crozier admitted his misgivings about the expedition and confided his deep loneliness. As I developed these plans, I repeatedly pictured Crozier writing alone in his uncomfortable little cabin, the most probable place for him to put down a very private last letter to his best friend.

References:

Ross, Sir James Clark

1847A Voyage of Discovery and Research in the Southern and Antarctic Regions, During the Years 1839-1843: Volume I. John Murray, London.

Monday, 1 September 2014

In late May I began a new sub-project of my build - creating an accurate plan of HMS Terror’s lower deck. I thought the project would take a few weeks at most, but creating this plan turned out to be a three month ordeal requiring minute scrutiny of multiple plans and significant research on mid-19th century deck furniture and fittings. The task was made easier by Peter Carney and William Battersby who kindly assisted me with translating some annotations on the plans. The difficulty in this project stems from the multiple versions of plans for HMS Terror, some of which are heavily annotated. There are three versions of just the Terror’s lower deck plans, including: 1) the initial 1813 lower deck plan (ZAZ5616), 2) the 1839 plan which shows both HMS Terror and Erebus, and 3) the 1836 plan, which was modified extensively in 1845 (ZAZ5676). In addition, critical information was gleaned from the 1839 midships section plan (ZAZ5678).I began by tracing the 1836 plan, and spent nearly a month interpreting the faint 1845 annotations which outline changes to the position of the cabins and a system of hatches and scuttles to accommodate the new engine room in the hold. I then carefully added information on deck furniture from the 1839 plan, and structural details from the 1813 plans. Finally, I compared the new plans to the inboard profile plans I previously created to ensure the accuracy of both (this indicated that some changes were needed on the inboard profile plans). I also created a series of detailed elevation plans for the crew accommodations and various fittings, some of which I will post over the coming weeks. HMS Investigator plans were very useful in this regard, as they provide important details that are not shown on the Erebus and Terror plans. Additionally, I found critical information on the appearance and construction of deck furniture from researching photos from HMS Unicorn, HMS Trincomalee, and HMS Warrior. Following research outlined in previous blog posts, I assume that most of HMS Terror’s 1845 fittings conformed to specifications outlined on the 1839 Terror and Erebus plans. Parry’s rationale for identically outfitting polar expeditions notwithstanding, I believe the Admiralty learned important lessons from the near- disastrous 1836 Back expedition (see a description of the damage to the ship here), and decided that critical structural improvements were necessary for all arctic bomb-discovery vessels. Thus, the 1839 plans are titled “Terror and Erebus as Fitted” because both ships were meant to be outfitted to precisely the same standards. These new systems proved themselves in the highly successful antarctic expedition, and by the time they sailed north in 1845, further improvements meant that both ships represented the state of the art in nautical science. While the project took far longer than anticipated, I greatly enjoyed producing these plans, as they provide insights into what the long winters in the ice were like for Crozier and his crew, nearly 170 years ago. Indeed, the ability to put a name to a specific cabin was a moving revelation; for example, Lieutenant Irving's description of the “dreadful puffings and screamings” of the locomotive engine (Bell 1881: 117) takes on new meaning when one realizes his cabin was almost directly above it! References:Bell, Benjamin1881Lieut. John Irving, R.N. of H.M.S. "Terror" in Sir John Franklin's Last Expedition to the Arctic Regions: A Memorial Sketch With Letters. D. Douglas, Edinburgh.

Lower Deck, HMS Terror, 1845

(note the presence of the large central sail bin on Terror, needed to accommodate the

Sunday, 29 June 2014

Today marks the 201st
anniversary of the launch of HMS Terror in Topsham, Devon. It also marks the first anniversary of Building Terror. I envision the blog as a
place to document the history and architecture of one of the world’s greatest polar
exploration ships. I’m telling that story through my project to
build the world’s first accurate model of the Terror as she appeared in 1845.

I’ve been very pleased with the public response
to the blog, which has received nearly 10,000 views in the last year. It has led
me to correspond with some of the foremost scholars of both the Franklin
Expedition and historic sailing vessels of the 18th and 19th
centuries.

I research each part of the vessel in detail
as I build, so construction of the model has proceeded slowly, but on pace. I have duplicated much of the blog in a topic on Model Ship World forums, and the comments of the modelers, who are some
of the world’s most knowledgeable ship historians, will likely be of interest
to followers of this blog.

Building Terror has been accessed all over
the world, and my images and plans have popped up in numerous places, most notably
on the exhibit website for “HMS
Terror: A Topsham Boat”, hosted at the Topsham Museum
(Devon Museums).

I’ve had many requests for plans, images, and
even the model itself; others have asked me to write research papers or a
book on the architecture of the ship. For now my goal is simply to finish my plans
and model. When they are complete and accurate, I’ll decide what to do
next. If you have any ideas, I’d be
happy to hear them.

The many hundreds of hours I’ve spent
pouring over plans and researching this fascinating ship have been some of the most
rewarding I can recall. The Terror really was something else altogether– in her time, she was the pinnacle
of nautical science; the embodiment of the desire to explore,
document, and dominate the natural world; and the emblem of an empire’s dominion. Alone in the ice, she was the incarnation of the simple determination and
courage of men.

Even if she had never been part of the
Franklin voyage she would still have a place among the greatest exploration
vessels of all time. Yet Terror’s final two years sheltering her crew from the crushing
pack off King William Island proved her true mettle; there was nothing further
a polar exploration vessel could have achieved.

Some may say she didn't deserve
her fate. Her captain and crew certainly did not. But had she survived, she
would likely have been turned into a transport or scow and then broken up like HMS
Resolute. In whatever state she’s in, HMS Terror is still preserved somewhere
under the Arctic Ocean. The mystery of where she rests continues to draw us to
her. She deserves the attention.

Wednesday, 25 June 2014

As I’ve documented in previous
posts, HMS Terror’s stern well was to be filled with strengthening chocks
when the propeller wasn't in use. A unique feature of this design was described
by Oliver Lang, the shipwright in charge of the 1845 refit, as an “iron tank
placed over the chocks in which any small article of stores may be stored” (NMM
ZAZ5683 [J1529]). Lang’s 1845
plan, while vague, suggests that the tank was similar to iron storage tanks
used in Royal Navy ships of the era, with one major difference: the fore and
aft faces of the tank had two grooves running along their length to seat it on
the rails in the propeller well (see my previous post).

Iron tanks had been used in the Royal Navy since 1813 and were used to
store all manner of dry and wet goods, and were often used as ballast tanks
when stores were depleted or offloaded (Pearson 1992). An example of the types
of tanks used in the Franklin era can still be found in the excellently
preserved Dealy
Island Storehouse, constructed by Captain Kellett of HMS Resolute. The
storage tanks were iron, ca. 48 inches by 48 inches in size, with lines of rivets
along the middle and alternate edges of each face and around their circular
openings (Jane 1982: Figure 3, Figure 6). I copied this rivet pattern in my
reconstruction of the Terror’s stern tank.

The openings of
these tanks were sealed with a recessed cast iron lid, between 12 and 24 inches in diameter with a wire rod handle and a cork or wooden bung inserted into
a circular opening in their centre (Pearson 1992:24). Maudslay, Sons, and Field, who were contracted to supply
the engines installed in HMS Erebus and Terror (Battersby and Carney 2011:201),
owned the patent to produce ship's tanks (Pearson 1992:25), and it is reasonable
to assume that they built the custom stern tanks for the Franklin Expedition. If so, the "Maudslay, Sons, and Field" name
should be stamped on the cast iron lids for the tanks, if they are ever found
(e.g. Pearson 1992:26).

As can be
seen above, the profile dimensions of the Terror’s stern tank are shown on Lang’s
plan, as well as a general indication of the size and position of the lid and
two iron rings used to raise and lower the tank into position. The plans
indicate the tank had the following profile dimensions:

Height = 40 inches

Length (moulded) = 25 and ½
inches

I have
estimated, based on the distance between the stern frames, that the propeller
well and the tank were sided approximately 34 inches.

1982 The
Preservation and Ethnohistory of a Frozen Historic Site in the Canadian Arctic.
Arctic 35(3):358-385.

Battersby, William, and Carney, Peter

2011 Equipping HM Ships
Erebus and Terror, 1845. International
Journal for the History of Engineering and Technology 81(2):192-211.

Sheet brass scored prior to cutting.

A pounce wheel was used to mark the location of the rivets.

The rivets were simulated by punching the brass from the reverse side with the sharp end of a file.

The central opening and wire handle of the lid were made from brass tube and wire.

The outer rim of the lid was soldered into place. The central opening (right) was trimmed and soldered to a plate to form the bottom of the lid (wire still needs to be trimmed to length).

The completed lid soldered in place and cleaned up
(sanding is still required and the central hole needs to be drilled to remove the wire rod).

Rings for raising and lowering the tank soldered in place.

The tank parts after chemical blackening. The grooves were made from existing brass stock.

Soldering the entire tank was impossible, so a balsa form was created to glue the plates in place.

Starboard side glued in place.

The finished tank. The seams were glued, sanded and then painted to match the metal surface. The piece was then lightly coated in dewatering oil to simulate the laquer often used on the real tanks (and to prevent future corrosion).

Detail of the top of the tank. The bung in the lid was made with wood-filler.

The approximate position where the tank will sit in the well. I'm waiting for the oil to fully penetrate before I dry-fit the piece to the wood.

The tank seated on the propeller rails. When the rails are glued in place on the stern the tank can be placed in the well or on deck depending on how the model will be displayed (e.g. with propeller in place or not).